diff options
Diffstat (limited to 'lib/python2.7/site-packages/django/db/models/expressions.py')
| -rw-r--r-- | lib/python2.7/site-packages/django/db/models/expressions.py | 186 |
1 files changed, 0 insertions, 186 deletions
diff --git a/lib/python2.7/site-packages/django/db/models/expressions.py b/lib/python2.7/site-packages/django/db/models/expressions.py deleted file mode 100644 index 6e0f3c4..0000000 --- a/lib/python2.7/site-packages/django/db/models/expressions.py +++ /dev/null @@ -1,186 +0,0 @@ -import datetime - -from django.db.models.aggregates import refs_aggregate -from django.db.models.constants import LOOKUP_SEP -from django.utils import tree - -class ExpressionNode(tree.Node): - """ - Base class for all query expressions. - """ - # Arithmetic connectors - ADD = '+' - SUB = '-' - MUL = '*' - DIV = '/' - MOD = '%%' # This is a quoted % operator - it is quoted - # because it can be used in strings that also - # have parameter substitution. - - # Bitwise operators - note that these are generated by .bitand() - # and .bitor(), the '&' and '|' are reserved for boolean operator - # usage. - BITAND = '&' - BITOR = '|' - - def __init__(self, children=None, connector=None, negated=False): - if children is not None and len(children) > 1 and connector is None: - raise TypeError('You have to specify a connector.') - super(ExpressionNode, self).__init__(children, connector, negated) - - def _combine(self, other, connector, reversed, node=None): - if isinstance(other, datetime.timedelta): - return DateModifierNode([self, other], connector) - - if reversed: - obj = ExpressionNode([other], connector) - obj.add(node or self, connector) - else: - obj = node or ExpressionNode([self], connector) - obj.add(other, connector) - return obj - - def contains_aggregate(self, existing_aggregates): - if self.children: - return any(child.contains_aggregate(existing_aggregates) - for child in self.children - if hasattr(child, 'contains_aggregate')) - else: - return refs_aggregate(self.name.split(LOOKUP_SEP), - existing_aggregates) - - def prepare_database_save(self, unused): - return self - - ################### - # VISITOR METHODS # - ################### - - def prepare(self, evaluator, query, allow_joins): - return evaluator.prepare_node(self, query, allow_joins) - - def evaluate(self, evaluator, qn, connection): - return evaluator.evaluate_node(self, qn, connection) - - ############# - # OPERATORS # - ############# - - def __add__(self, other): - return self._combine(other, self.ADD, False) - - def __sub__(self, other): - return self._combine(other, self.SUB, False) - - def __mul__(self, other): - return self._combine(other, self.MUL, False) - - def __truediv__(self, other): - return self._combine(other, self.DIV, False) - - def __div__(self, other): # Python 2 compatibility - return type(self).__truediv__(self, other) - - def __mod__(self, other): - return self._combine(other, self.MOD, False) - - def __and__(self, other): - raise NotImplementedError( - "Use .bitand() and .bitor() for bitwise logical operations." - ) - - def bitand(self, other): - return self._combine(other, self.BITAND, False) - - def __or__(self, other): - raise NotImplementedError( - "Use .bitand() and .bitor() for bitwise logical operations." - ) - - def bitor(self, other): - return self._combine(other, self.BITOR, False) - - def __radd__(self, other): - return self._combine(other, self.ADD, True) - - def __rsub__(self, other): - return self._combine(other, self.SUB, True) - - def __rmul__(self, other): - return self._combine(other, self.MUL, True) - - def __rtruediv__(self, other): - return self._combine(other, self.DIV, True) - - def __rdiv__(self, other): # Python 2 compatibility - return type(self).__rtruediv__(self, other) - - def __rmod__(self, other): - return self._combine(other, self.MOD, True) - - def __rand__(self, other): - raise NotImplementedError( - "Use .bitand() and .bitor() for bitwise logical operations." - ) - - def __ror__(self, other): - raise NotImplementedError( - "Use .bitand() and .bitor() for bitwise logical operations." - ) - -class F(ExpressionNode): - """ - An expression representing the value of the given field. - """ - def __init__(self, name): - super(F, self).__init__(None, None, False) - self.name = name - - def __deepcopy__(self, memodict): - obj = super(F, self).__deepcopy__(memodict) - obj.name = self.name - return obj - - def prepare(self, evaluator, query, allow_joins): - return evaluator.prepare_leaf(self, query, allow_joins) - - def evaluate(self, evaluator, qn, connection): - return evaluator.evaluate_leaf(self, qn, connection) - -class DateModifierNode(ExpressionNode): - """ - Node that implements the following syntax: - filter(end_date__gt=F('start_date') + datetime.timedelta(days=3, seconds=200)) - - which translates into: - POSTGRES: - WHERE end_date > (start_date + INTERVAL '3 days 200 seconds') - - MYSQL: - WHERE end_date > (start_date + INTERVAL '3 0:0:200:0' DAY_MICROSECOND) - - ORACLE: - WHERE end_date > (start_date + INTERVAL '3 00:03:20.000000' DAY(1) TO SECOND(6)) - - SQLITE: - WHERE end_date > django_format_dtdelta(start_date, "+" "3", "200", "0") - (A custom function is used in order to preserve six digits of fractional - second information on sqlite, and to format both date and datetime values.) - - Note that microsecond comparisons are not well supported with MySQL, since - MySQL does not store microsecond information. - - Only adding and subtracting timedeltas is supported, attempts to use other - operations raise a TypeError. - """ - def __init__(self, children, connector, negated=False): - if len(children) != 2: - raise TypeError('Must specify a node and a timedelta.') - if not isinstance(children[1], datetime.timedelta): - raise TypeError('Second child must be a timedelta.') - if connector not in (self.ADD, self.SUB): - raise TypeError('Connector must be + or -, not %s' % connector) - super(DateModifierNode, self).__init__(children, connector, negated) - - def evaluate(self, evaluator, qn, connection): - return evaluator.evaluate_date_modifier_node(self, qn, connection) |